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// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
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// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
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// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author: wan@google.com (Zhanyong Wan)

// Google Test - The Google C++ Testing Framework
//
// This file implements a universal value printer that can print a
// value of any type T:
//
//   void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr);
//
// A user can teach this function how to print a class type T by
// defining either operator<<() or PrintTo() in the namespace that
// defines T.  More specifically, the FIRST defined function in the
// following list will be used (assuming T is defined in namespace
// foo):
//
//   1. foo::PrintTo(const T&, ostream*)
//   2. operator<<(ostream&, const T&) defined in either foo or the
//      global namespace.
//
// If none of the above is defined, it will print the debug string of
// the value if it is a protocol buffer, or print the raw bytes in the
// value otherwise.
//
// To aid debugging: when T is a reference type, the address of the
// value is also printed; when T is a (const) char pointer, both the
// pointer value and the NUL-terminated string it points to are
// printed.
//
// We also provide some convenient wrappers:
//
//   // Prints a value to a string.  For a (const or not) char
//   // pointer, the NUL-terminated string (but not the pointer) is
//   // printed.
//   std::string ::testing::PrintToString(const T& value);
//
//   // Prints a value tersely: for a reference type, the referenced
//   // value (but not the address) is printed; for a (const or not) char
//   // pointer, the NUL-terminated string (but not the pointer) is
//   // printed.
//   void ::testing::internal::UniversalTersePrint(const T& value, ostream*);
//
//   // Prints value using the type inferred by the compiler.  The difference
//   // from UniversalTersePrint() is that this function prints both the
//   // pointer and the NUL-terminated string for a (const or not) char pointer.
//   void ::testing::internal::UniversalPrint(const T& value, ostream*);
//
//   // Prints the fields of a tuple tersely to a string vector, one
//   // element for each field. Tuple support must be enabled in
//   // gtest-port.h.
//   std::vector<string> UniversalTersePrintTupleFieldsToStrings(
//       const Tuple& value);
//
// Known limitation:
//
// The print primitives print the elements of an STL-style container
// using the compiler-inferred type of *iter where iter is a
// const_iterator of the container.  When const_iterator is an input
// iterator but not a forward iterator, this inferred type may not
// match value_type, and the print output may be incorrect.  In
// practice, this is rarely a problem as for most containers
// const_iterator is a forward iterator.  We'll fix this if there's an
// actual need for it.  Note that this fix cannot rely on value_type
// being defined as many user-defined container types don't have
// value_type.

#ifndef GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
#define GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_

#include <ostream>  // NOLINT
#include <sstream>
#include <string>
#include <utility>
#include <vector>
#include "gtest/internal/gtest-port.h"
#include "gtest/internal/gtest-internal.h"

namespace testing
{

    // Definitions in the 'internal' and 'internal2' name spaces are
    // subject to change without notice.  DO NOT USE THEM IN USER CODE!
    namespace internal2
    {

        // Prints the given number of bytes in the given object to the given
        // ostream.
        GTEST_API_ void PrintBytesInObjectTo(const unsigned char *obj_bytes,
                                             size_t count,
                                             ::std::ostream *os);

        // For selecting which printer to use when a given type has neither <<
        // nor PrintTo().
        enum TypeKind
        {
            kProtobuf,              // a protobuf type
            kConvertibleToInteger,  // a type implicitly convertible to BiggestInt
            // (e.g. a named or unnamed enum type)
            kOtherType              // anything else
        };

        // TypeWithoutFormatter<T, kTypeKind>::PrintValue(value, os) is called
        // by the universal printer to print a value of type T when neither
        // operator<< nor PrintTo() is defined for T, where kTypeKind is the
        // "kind" of T as defined by enum TypeKind.
        template <typename T, TypeKind kTypeKind>
        class TypeWithoutFormatter
        {
        public:
            // This default version is called when kTypeKind is kOtherType.
            static void PrintValue(const T &value, ::std::ostream *os)
            {
                PrintBytesInObjectTo(reinterpret_cast<const unsigned char *>(&value),
                                     sizeof(value), os);
            }
        };

        // We print a protobuf using its ShortDebugString() when the string
        // doesn't exceed this many characters; otherwise we print it using
        // DebugString() for better readability.
        const size_t kProtobufOneLinerMaxLength = 50;

        template <typename T>
        class TypeWithoutFormatter<T, kProtobuf>
        {
        public:
            static void PrintValue(const T &value, ::std::ostream *os)
            {
                const ::testing::internal::string short_str = value.ShortDebugString();
                const ::testing::internal::string pretty_str =
                    short_str.length() <= kProtobufOneLinerMaxLength ?
                    short_str : ("\n" + value.DebugString());
                *os << ("<" + pretty_str + ">");
            }
        };

        template <typename T>
        class TypeWithoutFormatter<T, kConvertibleToInteger>
        {
        public:
            // Since T has no << operator or PrintTo() but can be implicitly
            // converted to BiggestInt, we print it as a BiggestInt.
            //
            // Most likely T is an enum type (either named or unnamed), in which
            // case printing it as an integer is the desired behavior.  In case
            // T is not an enum, printing it as an integer is the best we can do
            // given that it has no user-defined printer.
            static void PrintValue(const T &value, ::std::ostream *os)
            {
                const internal::BiggestInt kBigInt = value;
                *os << kBigInt;
            }
        };

        // Prints the given value to the given ostream.  If the value is a
        // protocol message, its debug string is printed; if it's an enum or
        // of a type implicitly convertible to BiggestInt, it's printed as an
        // integer; otherwise the bytes in the value are printed.  This is
        // what UniversalPrinter<T>::Print() does when it knows nothing about
        // type T and T has neither << operator nor PrintTo().
        //
        // A user can override this behavior for a class type Foo by defining
        // a << operator in the namespace where Foo is defined.
        //
        // We put this operator in namespace 'internal2' instead of 'internal'
        // to simplify the implementation, as much code in 'internal' needs to
        // use << in STL, which would conflict with our own << were it defined
        // in 'internal'.
        //
        // Note that this operator<< takes a generic std::basic_ostream<Char,
        // CharTraits> type instead of the more restricted std::ostream.  If
        // we define it to take an std::ostream instead, we'll get an
        // "ambiguous overloads" compiler error when trying to print a type
        // Foo that supports streaming to std::basic_ostream<Char,
        // CharTraits>, as the compiler cannot tell whether
        // operator<<(std::ostream&, const T&) or
        // operator<<(std::basic_stream<Char, CharTraits>, const Foo&) is more
        // specific.
        template <typename Char, typename CharTraits, typename T>
        ::std::basic_ostream<Char, CharTraits>& operator<<(
            ::std::basic_ostream<Char, CharTraits>& os, const T &x)
        {
            TypeWithoutFormatter < T,
                                 (internal::IsAProtocolMessage<T>::value ? kProtobuf :
                                  internal::ImplicitlyConvertible<const T &, internal::BiggestInt>::value ?
                                  kConvertibleToInteger : kOtherType) >::PrintValue(x, &os);
            return os;
        }

    }  // namespace internal2
}  // namespace testing

// This namespace MUST NOT BE NESTED IN ::testing, or the name look-up
// magic needed for implementing UniversalPrinter won't work.
namespace testing_internal
{

    // Used to print a value that is not an STL-style container when the
    // user doesn't define PrintTo() for it.
    template <typename T>
    void DefaultPrintNonContainerTo(const T &value, ::std::ostream *os)
    {
        // With the following statement, during unqualified name lookup,
        // testing::internal2::operator<< appears as if it was declared in
        // the nearest enclosing namespace that contains both
        // ::testing_internal and ::testing::internal2, i.e. the global
        // namespace.  For more details, refer to the C++ Standard section
        // 7.3.4-1 [namespace.udir].  This allows us to fall back onto
        // testing::internal2::operator<< in case T doesn't come with a <<
        // operator.
        //
        // We cannot write 'using ::testing::internal2::operator<<;', which
        // gcc 3.3 fails to compile due to a compiler bug.
        using namespace ::testing::internal2;  // NOLINT
        // Assuming T is defined in namespace foo, in the next statement,
        // the compiler will consider all of:
        //
        //   1. foo::operator<< (thanks to Koenig look-up),
        //   2. ::operator<< (as the current namespace is enclosed in ::),
        //   3. testing::internal2::operator<< (thanks to the using statement above).
        //
        // The operator<< whose type matches T best will be picked.
        //
        // We deliberately allow #2 to be a candidate, as sometimes it's
        // impossible to define #1 (e.g. when foo is ::std, defining
        // anything in it is undefined behavior unless you are a compiler
        // vendor.).
        *os << value;
    }

}  // namespace testing_internal

namespace testing
{
    namespace internal
    {

        // UniversalPrinter<T>::Print(value, ostream_ptr) prints the given
        // value to the given ostream.  The caller must ensure that
        // 'ostream_ptr' is not NULL, or the behavior is undefined.
        //
        // We define UniversalPrinter as a class template (as opposed to a
        // function template), as we need to partially specialize it for
        // reference types, which cannot be done with function templates.
        template <typename T>
        class UniversalPrinter;

        template <typename T>
        void UniversalPrint(const T &value, ::std::ostream *os);

        // Used to print an STL-style container when the user doesn't define
        // a PrintTo() for it.
        template <typename C>
        void DefaultPrintTo(IsContainer /* dummy */,
                            false_type /* is not a pointer */,
                            const C &container, ::std::ostream *os)
        {
            const size_t kMaxCount = 32;  // The maximum number of elements to print.
            *os << '{';
            size_t count = 0;

            for (typename C::const_iterator it = container.begin();
                    it != container.end(); ++it, ++count)
            {
                if (count > 0)
                {
                    *os << ',';

                    if (count == kMaxCount)    // Enough has been printed.
                    {
                        *os << " ...";
                        break;
                    }
                }

                *os << ' ';
                // We cannot call PrintTo(*it, os) here as PrintTo() doesn't
                // handle *it being a native array.
                internal::UniversalPrint(*it, os);
            }

            if (count > 0)
            {
                *os << ' ';
            }

            *os << '}';
        }

        // Used to print a pointer that is neither a char pointer nor a member
        // pointer, when the user doesn't define PrintTo() for it.  (A member
        // variable pointer or member function pointer doesn't really point to
        // a location in the address space.  Their representation is
        // implementation-defined.  Therefore they will be printed as raw
        // bytes.)
        template <typename T>
        void DefaultPrintTo(IsNotContainer /* dummy */,
                            true_type /* is a pointer */,
                            T *p, ::std::ostream *os)
        {
            if (p == NULL)
            {
                *os << "NULL";
            }
            else
            {
                // C++ doesn't allow casting from a function pointer to any object
                // pointer.
                //
                // IsTrue() silences warnings: "Condition is always true",
                // "unreachable code".
                if (IsTrue(ImplicitlyConvertible<T *, const void *>::value))
                {
                    // T is not a function type.  We just call << to print p,
                    // relying on ADL to pick up user-defined << for their pointer
                    // types, if any.
                    *os << p;
                }
                else
                {
                    // T is a function type, so '*os << p' doesn't do what we want
                    // (it just prints p as bool).  We want to print p as a const
                    // void*.  However, we cannot cast it to const void* directly,
                    // even using reinterpret_cast, as earlier versions of gcc
                    // (e.g. 3.4.5) cannot compile the cast when p is a function
                    // pointer.  Casting to UInt64 first solves the problem.
                    *os << reinterpret_cast<const void *>(
                            reinterpret_cast<internal::UInt64>(p));
                }
            }
        }

        // Used to print a non-container, non-pointer value when the user
        // doesn't define PrintTo() for it.
        template <typename T>
        void DefaultPrintTo(IsNotContainer /* dummy */,
                            false_type /* is not a pointer */,
                            const T &value, ::std::ostream *os)
        {
            ::testing_internal::DefaultPrintNonContainerTo(value, os);
        }

        // Prints the given value using the << operator if it has one;
        // otherwise prints the bytes in it.  This is what
        // UniversalPrinter<T>::Print() does when PrintTo() is not specialized
        // or overloaded for type T.
        //
        // A user can override this behavior for a class type Foo by defining
        // an overload of PrintTo() in the namespace where Foo is defined.  We
        // give the user this option as sometimes defining a << operator for
        // Foo is not desirable (e.g. the coding style may prevent doing it,
        // or there is already a << operator but it doesn't do what the user
        // wants).
        template <typename T>
        void PrintTo(const T &value, ::std::ostream *os)
        {
            // DefaultPrintTo() is overloaded.  The type of its first two
            // arguments determine which version will be picked.  If T is an
            // STL-style container, the version for container will be called; if
            // T is a pointer, the pointer version will be called; otherwise the
            // generic version will be called.
            //
            // Note that we check for container types here, prior to we check
            // for protocol message types in our operator<<.  The rationale is:
            //
            // For protocol messages, we want to give people a chance to
            // override Google Mock's format by defining a PrintTo() or
            // operator<<.  For STL containers, other formats can be
            // incompatible with Google Mock's format for the container
            // elements; therefore we check for container types here to ensure
            // that our format is used.
            //
            // The second argument of DefaultPrintTo() is needed to bypass a bug
            // in Symbian's C++ compiler that prevents it from picking the right
            // overload between:
            //
            //   PrintTo(const T& x, ...);
            //   PrintTo(T* x, ...);
            DefaultPrintTo(IsContainerTest<T>(0), is_pointer<T>(), value, os);
        }

        // The following list of PrintTo() overloads tells
        // UniversalPrinter<T>::Print() how to print standard types (built-in
        // types, strings, plain arrays, and pointers).

        // Overloads for various char types.
        GTEST_API_ void PrintTo(unsigned char c, ::std::ostream *os);
        GTEST_API_ void PrintTo(signed char c, ::std::ostream *os);
        inline void PrintTo(char c, ::std::ostream *os)
        {
            // When printing a plain char, we always treat it as unsigned.  This
            // way, the output won't be affected by whether the compiler thinks
            // char is signed or not.
            PrintTo(static_cast<unsigned char>(c), os);
        }

        // Overloads for other simple built-in types.
        inline void PrintTo(bool x, ::std::ostream *os)
        {
            *os << (x ? "true" : "false");
        }

        // Overload for wchar_t type.
        // Prints a wchar_t as a symbol if it is printable or as its internal
        // code otherwise and also as its decimal code (except for L'\0').
        // The L'\0' char is printed as "L'\\0'". The decimal code is printed
        // as signed integer when wchar_t is implemented by the compiler
        // as a signed type and is printed as an unsigned integer when wchar_t
        // is implemented as an unsigned type.
        GTEST_API_ void PrintTo(wchar_t wc, ::std::ostream *os);

        // Overloads for C strings.
        GTEST_API_ void PrintTo(const char *s, ::std::ostream *os);
        inline void PrintTo(char *s, ::std::ostream *os)
        {
            PrintTo(ImplicitCast_<const char *>(s), os);
        }

        // signed/unsigned char is often used for representing binary data, so
        // we print pointers to it as void* to be safe.
        inline void PrintTo(const signed char *s, ::std::ostream *os)
        {
            PrintTo(ImplicitCast_<const void *>(s), os);
        }
        inline void PrintTo(signed char *s, ::std::ostream *os)
        {
            PrintTo(ImplicitCast_<const void *>(s), os);
        }
        inline void PrintTo(const unsigned char *s, ::std::ostream *os)
        {
            PrintTo(ImplicitCast_<const void *>(s), os);
        }
        inline void PrintTo(unsigned char *s, ::std::ostream *os)
        {
            PrintTo(ImplicitCast_<const void *>(s), os);
        }

        // MSVC can be configured to define wchar_t as a typedef of unsigned
        // short.  It defines _NATIVE_WCHAR_T_DEFINED when wchar_t is a native
        // type.  When wchar_t is a typedef, defining an overload for const
        // wchar_t* would cause unsigned short* be printed as a wide string,
        // possibly causing invalid memory accesses.
#if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
        // Overloads for wide C strings
        GTEST_API_ void PrintTo(const wchar_t *s, ::std::ostream *os);
        inline void PrintTo(wchar_t *s, ::std::ostream *os)
        {
            PrintTo(ImplicitCast_<const wchar_t *>(s), os);
        }
#endif

        // Overload for C arrays.  Multi-dimensional arrays are printed
        // properly.

        // Prints the given number of elements in an array, without printing
        // the curly braces.
        template <typename T>
        void PrintRawArrayTo(const T a[], size_t count, ::std::ostream *os)
        {
            UniversalPrint(a[0], os);

            for (size_t i = 1; i != count; i++)
            {
                *os << ", ";
                UniversalPrint(a[i], os);
            }
        }

        // Overloads for ::string and ::std::string.
#if GTEST_HAS_GLOBAL_STRING
        GTEST_API_ void PrintStringTo(const ::string &s, ::std::ostream *os);
        inline void PrintTo(const ::string &s, ::std::ostream *os)
        {
            PrintStringTo(s, os);
        }
#endif  // GTEST_HAS_GLOBAL_STRING

        GTEST_API_ void PrintStringTo(const ::std::string &s, ::std::ostream *os);
        inline void PrintTo(const ::std::string &s, ::std::ostream *os)
        {
            PrintStringTo(s, os);
        }

        // Overloads for ::wstring and ::std::wstring.
#if GTEST_HAS_GLOBAL_WSTRING
        GTEST_API_ void PrintWideStringTo(const ::wstring &s, ::std::ostream *os);
        inline void PrintTo(const ::wstring &s, ::std::ostream *os)
        {
            PrintWideStringTo(s, os);
        }
#endif  // GTEST_HAS_GLOBAL_WSTRING

#if GTEST_HAS_STD_WSTRING
        GTEST_API_ void PrintWideStringTo(const ::std::wstring &s, ::std::ostream *os);
        inline void PrintTo(const ::std::wstring &s, ::std::ostream *os)
        {
            PrintWideStringTo(s, os);
        }
#endif  // GTEST_HAS_STD_WSTRING

#if GTEST_HAS_TR1_TUPLE
        // Overload for ::std::tr1::tuple.  Needed for printing function arguments,
        // which are packed as tuples.

        // Helper function for printing a tuple.  T must be instantiated with
        // a tuple type.
        template <typename T>
        void PrintTupleTo(const T &t, ::std::ostream *os);

        // Overloaded PrintTo() for tuples of various arities.  We support
        // tuples of up-to 10 fields.  The following implementation works
        // regardless of whether tr1::tuple is implemented using the
        // non-standard variadic template feature or not.

        inline void PrintTo(const ::std::tr1::tuple<>& t, ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template <typename T1>
        void PrintTo(const ::std::tr1::tuple<T1>& t, ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template <typename T1, typename T2>
        void PrintTo(const ::std::tr1::tuple<T1, T2>& t, ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template <typename T1, typename T2, typename T3>
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3>& t, ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template <typename T1, typename T2, typename T3, typename T4>
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4>& t, ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template <typename T1, typename T2, typename T3, typename T4, typename T5>
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5>& t,
                     ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template < typename T1, typename T2, typename T3, typename T4, typename T5,
                 typename T6 >
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6>& t,
                     ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template < typename T1, typename T2, typename T3, typename T4, typename T5,
                 typename T6, typename T7 >
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7>& t,
                     ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template < typename T1, typename T2, typename T3, typename T4, typename T5,
                 typename T6, typename T7, typename T8 >
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8>& t,
                     ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template < typename T1, typename T2, typename T3, typename T4, typename T5,
                 typename T6, typename T7, typename T8, typename T9 >
        void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8, T9>& t,
                     ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }

        template < typename T1, typename T2, typename T3, typename T4, typename T5,
                 typename T6, typename T7, typename T8, typename T9, typename T10 >
        void PrintTo(
            const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>& t,
            ::std::ostream *os)
        {
            PrintTupleTo(t, os);
        }
#endif  // GTEST_HAS_TR1_TUPLE

        // Overload for std::pair.
        template <typename T1, typename T2>
        void PrintTo(const ::std::pair<T1, T2>& value, ::std::ostream *os)
        {
            *os << '(';
            // We cannot use UniversalPrint(value.first, os) here, as T1 may be
            // a reference type.  The same for printing value.second.
            UniversalPrinter<T1>::Print(value.first, os);
            *os << ", ";
            UniversalPrinter<T2>::Print(value.second, os);
            *os << ')';
        }

        // Implements printing a non-reference type T by letting the compiler
        // pick the right overload of PrintTo() for T.
        template <typename T>
        class UniversalPrinter
        {
        public:
            // MSVC warns about adding const to a function type, so we want to
            // disable the warning.
#ifdef _MSC_VER
# pragma warning(push)          // Saves the current warning state.
# pragma warning(disable:4180)  // Temporarily disables warning 4180.
#endif  // _MSC_VER

            // Note: we deliberately don't call this PrintTo(), as that name
            // conflicts with ::testing::internal::PrintTo in the body of the
            // function.
            static void Print(const T &value, ::std::ostream *os)
            {
                // By default, ::testing::internal::PrintTo() is used for printing
                // the value.
                //
                // Thanks to Koenig look-up, if T is a class and has its own
                // PrintTo() function defined in its namespace, that function will
                // be visible here.  Since it is more specific than the generic ones
                // in ::testing::internal, it will be picked by the compiler in the
                // following statement - exactly what we want.
                PrintTo(value, os);
            }

#ifdef _MSC_VER
# pragma warning(pop)           // Restores the warning state.
#endif  // _MSC_VER
        };

        // UniversalPrintArray(begin, len, os) prints an array of 'len'
        // elements, starting at address 'begin'.
        template <typename T>
        void UniversalPrintArray(const T *begin, size_t len, ::std::ostream *os)
        {
            if (len == 0)
            {
                *os << "{}";
            }
            else
            {
                *os << "{ ";
                const size_t kThreshold = 18;
                const size_t kChunkSize = 8;

                // If the array has more than kThreshold elements, we'll have to
                // omit some details by printing only the first and the last
                // kChunkSize elements.
                // TODO(wan@google.com): let the user control the threshold using a flag.
                if (len <= kThreshold)
                {
                    PrintRawArrayTo(begin, len, os);
                }
                else
                {
                    PrintRawArrayTo(begin, kChunkSize, os);
                    *os << ", ..., ";
                    PrintRawArrayTo(begin + len - kChunkSize, kChunkSize, os);
                }

                *os << " }";
            }
        }
        // This overload prints a (const) char array compactly.
        GTEST_API_ void UniversalPrintArray(const char *begin,
                                            size_t len,
                                            ::std::ostream *os);

        // Implements printing an array type T[N].
        template <typename T, size_t N>
        class UniversalPrinter<T[N]>
        {
        public:
            // Prints the given array, omitting some elements when there are too
            // many.
            static void Print(const T(&a)[N], ::std::ostream *os)
            {
                UniversalPrintArray(a, N, os);
            }
        };

        // Implements printing a reference type T&.
        template <typename T>
        class UniversalPrinter<T &>
        {
        public:
            // MSVC warns about adding const to a function type, so we want to
            // disable the warning.
#ifdef _MSC_VER
# pragma warning(push)          // Saves the current warning state.
# pragma warning(disable:4180)  // Temporarily disables warning 4180.
#endif  // _MSC_VER

            static void Print(const T &value, ::std::ostream *os)
            {
                // Prints the address of the value.  We use reinterpret_cast here
                // as static_cast doesn't compile when T is a function type.
                *os << "@" << reinterpret_cast<const void *>(&value) << " ";
                // Then prints the value itself.
                UniversalPrint(value, os);
            }

#ifdef _MSC_VER
# pragma warning(pop)           // Restores the warning state.
#endif  // _MSC_VER
        };

        // Prints a value tersely: for a reference type, the referenced value
        // (but not the address) is printed; for a (const) char pointer, the
        // NUL-terminated string (but not the pointer) is printed.
        template <typename T>
        void UniversalTersePrint(const T &value, ::std::ostream *os)
        {
            UniversalPrint(value, os);
        }
        inline void UniversalTersePrint(const char *str, ::std::ostream *os)
        {
            if (str == NULL)
            {
                *os << "NULL";
            }
            else
            {
                UniversalPrint(string(str), os);
            }
        }
        inline void UniversalTersePrint(char *str, ::std::ostream *os)
        {
            UniversalTersePrint(static_cast<const char *>(str), os);
        }

        // Prints a value using the type inferred by the compiler.  The
        // difference between this and UniversalTersePrint() is that for a
        // (const) char pointer, this prints both the pointer and the
        // NUL-terminated string.
        template <typename T>
        void UniversalPrint(const T &value, ::std::ostream *os)
        {
            UniversalPrinter<T>::Print(value, os);
        }

#if GTEST_HAS_TR1_TUPLE
        typedef ::std::vector<string> Strings;

        // This helper template allows PrintTo() for tuples and
        // UniversalTersePrintTupleFieldsToStrings() to be defined by
        // induction on the number of tuple fields.  The idea is that
        // TuplePrefixPrinter<N>::PrintPrefixTo(t, os) prints the first N
        // fields in tuple t, and can be defined in terms of
        // TuplePrefixPrinter<N - 1>.

        // The inductive case.
        template <size_t N>
        struct TuplePrefixPrinter
        {
            // Prints the first N fields of a tuple.
            template <typename Tuple>
            static void PrintPrefixTo(const Tuple &t, ::std::ostream *os)
            {
                TuplePrefixPrinter < N - 1 >::PrintPrefixTo(t, os);
                *os << ", ";
                UniversalPrinter < typename ::std::tr1::tuple_element < N - 1, Tuple >::type >
                ::Print(::std::tr1::get < N - 1 > (t), os);
            }

            // Tersely prints the first N fields of a tuple to a string vector,
            // one element for each field.
            template <typename Tuple>
            static void TersePrintPrefixToStrings(const Tuple &t, Strings *strings)
            {
                TuplePrefixPrinter < N - 1 >::TersePrintPrefixToStrings(t, strings);
                ::std::stringstream ss;
                UniversalTersePrint(::std::tr1::get < N - 1 > (t), &ss);
                strings->push_back(ss.str());
            }
        };

        // Base cases.
        template <>
        struct TuplePrefixPrinter<0>
        {
            template <typename Tuple>
            static void PrintPrefixTo(const Tuple &, ::std::ostream *) {}

            template <typename Tuple>
            static void TersePrintPrefixToStrings(const Tuple &, Strings *) {}
        };
        // We have to specialize the entire TuplePrefixPrinter<> class
        // template here, even though the definition of
        // TersePrintPrefixToStrings() is the same as the generic version, as
        // Embarcadero (formerly CodeGear, formerly Borland) C++ doesn't
        // support specializing a method template of a class template.
        template <>
        struct TuplePrefixPrinter<1>
        {
            template <typename Tuple>
            static void PrintPrefixTo(const Tuple &t, ::std::ostream *os)
            {
                UniversalPrinter<typename ::std::tr1::tuple_element<0, Tuple>::type>::
                Print(::std::tr1::get<0>(t), os);
            }

            template <typename Tuple>
            static void TersePrintPrefixToStrings(const Tuple &t, Strings *strings)
            {
                ::std::stringstream ss;
                UniversalTersePrint(::std::tr1::get<0>(t), &ss);
                strings->push_back(ss.str());
            }
        };

        // Helper function for printing a tuple.  T must be instantiated with
        // a tuple type.
        template <typename T>
        void PrintTupleTo(const T &t, ::std::ostream *os)
        {
            *os << "(";
            TuplePrefixPrinter< ::std::tr1::tuple_size<T>::value>::
            PrintPrefixTo(t, os);
            *os << ")";
        }

        // Prints the fields of a tuple tersely to a string vector, one
        // element for each field.  See the comment before
        // UniversalTersePrint() for how we define "tersely".
        template <typename Tuple>
        Strings UniversalTersePrintTupleFieldsToStrings(const Tuple &value)
        {
            Strings result;
            TuplePrefixPrinter< ::std::tr1::tuple_size<Tuple>::value>::
            TersePrintPrefixToStrings(value, &result);
            return result;
        }
#endif  // GTEST_HAS_TR1_TUPLE

    }  // namespace internal

    template <typename T>
    ::std::string PrintToString(const T &value)
    {
        ::std::stringstream ss;
        internal::UniversalTersePrint(value, &ss);
        return ss.str();
    }

}  // namespace testing

#endif  // GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
